1. Field of the Invention
The present invention relates to a recording medium cartridge having identification information for identifying the recording medium, a recording/reproducing apparatus which operates with such a cartridge, and an information management system which includes a plurality of recording medium cartridges and which records or reproduces information on or from the recording medium of a particular recording medium cartridge in response to a command given from an external controller.
2. Description of the Related Art
A recording medium such as a magnetic disk (hard disk, flexible disk) or a magnetic tape is widely used in a computer system. An information management system is known in the art which manages information by recording and reproducing a great amount of information on or from recording media via a plurality of drive units.
In an information management system using magnetic tapes serving as recording media (hereinafter referred to as a tape library system), a great number of tape cassettes are placed in a rack, and a desired tape cassette is taken, as required, out of the rack by a transfer mechanism and it is loaded on a tape drive unit properly selected from a plurality of tape drive units thereby recording or reproducing information.
The tape library system includes control means which communicates with an external control device such as a host computer. In response to a command from the external control device, the tape library system reproduces requested information from a magnetic tape via a tape drive unit and provides the reproduced information to the external control device, or records information on a magnetic tape.
If such a tape library system includes a great number of, and various types of, tape cassettes each containing a magnetic tape, it is necessary to manage tape cassettes in accordance with not only the contents of information stored on the magnetic tape of each tape cassette but also identification information for identifying each tape cassette (such as the title, the type, and the format of each tape cassette) indicated on the outer surface of each tape cassette.
One known technique to meet the above requirement is to put a bar code label indicating identification information on each tape cassette in a similar manner to bar code information provided on books for managing a book library so that the bar code information is read by a reader provided on a tape cassette recording/reproducing apparatus thereby managing the tape cassettes.
However, the bar code label provided on the outer surface of a tape cassette is degraded after long-time use. The degradation can result in difficulty of reading the identification information, and thus it becomes necessary to read it a great number of times. At worst, it becomes impossible to read identification information at all.
When degradation occurs to a great extent, it is needed to replace the bar code label with a new label by a manual operation which is very troublesome. For example, if a bar code label is degraded to such a degree that no information can be read by visual inspection, it is required to put a correct bar code label on a tape cassette after checking the content of the tape cassette.